Peel the pumpkin and the purple potato, cut them into cube, steam them or boil them.
Blend together the steamed pumpkin, the white beans, and the sugar, until you have a very smooth paste.
MAKE THE DOUGH
Blend together the purple potato, the water, and the sugar. Let cool to 35˚C | 95˚F or you will kill the yeast. You can substitute red beet if you don't find purple potatoes.
In a bowl, mix together the flour, the purple liquid, the active dry yeast, the salt, the sugar, and knead for about 5 minutes, or until the ingredients are well incorporated.
Cover with a cloth and let proof for about 1 hour, or until it double in size.
Cut the dough into 8 equal pieces. Then start making the buns. See video for clarity.
Once shaped, let the buns proof for another 20 minutes.
Bake in the over at 150˚C | 300˚F for 20 minutes. Let them cool down and remove the string before eating them.
You can add some pumpkin seeds on top to make the stem.